Evaluation of Indigofera tinctoria L. for yield and glycoside content: under open and shaded conditions

Botanical natural products such as colours, drugs, flavours and foodstuffs are gaining importance worldwide. Indian indigo, a medicinally and commercially useful leguminous plant, cultivated in the East, mainly India and China is a potential source of indigo - a commercially valuable dye. The leaf extract has remarkable effect on hair growth and prevents juvenile greying of hair. In this study, thirty geographical accessions of indigo were collected from different locations and were grown under open and shaded conditions. Growth and yield parameters and glycoside content were found better under open condition compared to shade. Leaf yield had high positive correlation with parameters such as shoot yield, stem girth, leaf area and dry matter accumulation per plant. Negative correlation was observed with glycoside and indigo content. These traits are therefore highly amenable to direct selection for genetic improvement. Benefit - Cost analysis indicated that the crop can be cultivated as a profitable enterprise both under open and shade, the net income being less under shade. Out of the thirty accessions studied, three were found superior based on leaf yield and glycoside content.